Photographic film processing apparatus

ABSTRACT

A film advancing-fluid spreading apparatus for use in camera systems of the self-developing type. A spread roller assembly comprises first and second rotatably mounted juxtaposed elongated rollers that are yieldably urged one towards the other. A pair of annular collars provided on the first roller define a minimum gap between the rollers to facilitate the initial introduction of a leading edge of a film unit therebetween. This first roller is adapted to be selectively driven by a motor of the camera system and, when so driven, its annular collars impart a rotary motion to the second roller. At least those portions of the two rollers adapted to contact one another are formed of a relatively low friction, impact resistant material, such as a stainless steel, while at least the sheet-contacting facing surface of the first roller is formed of a relatively high friction material such as urethane.

United States Patent [1 1 1 Oct. 23, 1973 Whall PHOTOGRAPHIC FILMPROCESSING APPARATUS [75] Inventor: James M. Whall, Lexington, Mass.

[73] Assignee: Polaroid Corporation, Cambridge,

Mass.

[22] Filed: Apr. 24, 1972 [21] App1.No.: 246,750

[52] US. Cl. 95/89 A, 95/13 [51] Int. Cl. G031! 9/02 [58] Field ofSearch 95/89 R, 89 A, 89 L,

[56] References Cited UNITED STATES PATENTS 3,625,130 12/1971 Van Allenet al 95/89 L X 3,283,688 11/1966 Gold et al. 95/13 X 2,719,472 10/1955Land 95/13 X 2,638,828 5/1953 Bachelder et al. 95/89 L 3,327,599 6/1967Murphy 95 13 3,643,565 2/1972 Bellows 95/13 X Primary Examiner-Fred L.Braun Attorney-Robert L. Berger et al.

57 ABSTRACT A film advancing-fluid spreading apparatus for use in camerasystems of the self-developing type. A spread roller assembly comprisesfirst and second rotatably mounted juxtaposed elongated rollers that areyieldably urged one towards the other. A pair of annular collarsprovided on the first roller define a minimum gap between the rollers tofacilitate the initial introduction of a leading edge of a film unittherebetween. This first roller is adapted to be selectively driven by amotor of the camera system and, when so driven, its annular collarsimpart a rotary motion to the second roller. At least those portions ofthe two rollers adapted to contact one another are formed of arelatively low friction, impact resistant material, such as a stainlesssteel, while at least the sheet-contacting facing surface of the firstroller is formed of a relatively high friction material such asurethane.

3 Claims, 10 Drawing Figures PMENTEDIJBT23 1975 3, 766. 842

SHEET 1 [IF 4 3,766, 8&2

PAIENIEnnm 23 mm SHEET 8 OF 4 PATENTEDBBI 23 I873 EJ661342 sum u m aFIG. 6

.FIG'. 5

PHOTOGRAPIIIC FILM PROCESSING APPARATUS BACKGROUND OF THE INVENTION 1.Field of the Invention This invention relates to photography and, moreparticularly, to an improved film advancing-fluid spreading apparatus.

- 2. Description of the Prior Art The advantages of cameras of theself-developing type are well recognized. Commercially available camerasof this type provide fully developed black-andwhite photographs inapproximately seconds and fully developed photographs in full color inless than 7 one minute. While customer interest in these products is amatter of proven record, it is apparent that the market forself-developing camera systems can be significantly increased byeliminating and/or improving certain characteristics of the presentlyoffered products. For instance, it is desirable to further reduce thesize of suchcamera systems whenever this can be accomplished withoutreducing the size of the print which they produce. Also, it is desirableto provide systems which further simplify the task of the photographer.In this context, specially compact collapsible selfdevelopirig camerastructures have been heretofore devised. Typical of such structures arethose disclosed in US. Pat. No. 3,643,565 by Alfred H. Bellows entitledFOLDING CAMERA WITH DEVELOPING MEANS and in copending US. Pat.application Ser. No. 246,703 by Richard R. Wareham et al. entitled SELF-DEVELOPING CAMERA SYSTEM filed concurrently herewith. These particularsystems record an image of the scene of interest and provide thephotographer with a waste-free photograph of same responsive to theone-step operation of an actuator button. Film units typical of the typesuitable for use with those prior art camera structures are disclosed inUS. Pat. No. 3,415,644 by Edwin H. Land entitled NOVEL PHOTOGRAPHICPRODUCTS AND PROCESSES and in copending US. Pat. application Ser. No.194,407 by Edwin H. Land entitled NOVEL PROD- UCTS AND'PROCESSES filedon Nov. 1, 1971. One of the more critical elements in these particularcamera systems is their spread roller assembly which serves to rupturethe fluid containing pod of each film unit and to subsequently spreadthat fluid intermediate two selected elements or layers of the filmunit, while at the same time serving the function of advancing the filmunit through the spread roller assembly and exteriorly of the camerahousing. It is obviously important to further reduce the cost and sizeof such spread roller assemblies, and to further enhance theireffectiveness and reliability.

One of the objects of this invention therefore is to provide an improvedapparatus for treating an exposed film unit with a processing fluid.

Another primary object of this invention is to provide an improvedspreader roller apparatus of the film advancing type.

An additional object of the present invention is to provide spreaderroller apparatus of the type indicated having improved effectiveness andreliability.

A further object of this invention is to provide an improved spreaderroller arrangement of the type indicated wherein at least one roller hasa relatively high friction sheet-contacting facing surface, while atleast the portions of the rollers adapted to contact one anothercomprise relatively low friction, impact resistant surfaces.

SUMMARY OF THE INVENTION In its illustrated embodiment, the presentinvention is incorporated in a particularly compact selfdevelopingcamera structure of the collapsible type. The invention comprises a pairof rotatably mounted juxtaposed elongated rollers adapted to have arotary motion imparted thereto prior to engaging the leading edge of theexposed film unit. At least the sheetcontacting facing surface of oneroller is formed of a relatively high friction material such asurethane, while those portions of the two rollers adapted to contact oneanother are formed of a relatively low friction, impact resistantmaterial such as stainless steel.

In the preferred embodiment of the invention, a first roller comprises amain body portion, including a pair of spaced apart annular collars,formed of a suitable low friction, impact resistant material. Thesheetcontacting facing surface of this roller comprises a coating ofrelatively high friction material disposed on the main body portionintermediate the aforementioned annular collars. This first roller isconnected to a motor of the camera system. The second roller is formedof a relatively low friction, impact resistant material and is yieldablyurged towards the first roller by suitable spring means. In this manner,the annular collars of the first roller define a minimum gap between thesheet-contacting facing surfaces of the two rollers to facilitate theintroduction therebetween of the leading edge of an exposed film unit.Prior to the introduction ofa film unit into the bite of the rollers,rotary motion of the first roller is imparted to the second roller bythe annular collars. The relatively high friction sheet-contactingfacing surface enhances the film advancement characteristic of theroller assembly, while the relatively low friction, impact resistantcontacting surfaces of the two rollers enhance the structural integrityof the assembly when an exposed film unit clears the bite of the rollersand the second roller impacts against the annular collars of the firstroller responsive to the action of the aforementioned spring means.

BRIEF DESCRIPTION OF THE DRAWINGS The novel features that are consideredcharacteristic of the invention are set forth with particularity in theappended claims. The invention itself, however, both as to itsorganization and its method of operation, together with other objectsand advantages thereof, will be best understood from the followingdescription of the illustrated embodiment when read in connection withthe accompanying drawings wherein like numbers have been employed in thedifferent figures to denote the same parts and wherein:

FIG. 1 is a perspective view diagrammatically depict-- ing a collapsibleself-developing camera disposed in its operative condition andincorporating the present invention;

FIG. 2 is a perspective view of the camera of FIG. 1 disposed in itscollapsed or storage condition;

FIG. 3 is a diagrammatic, partially cut-away, side elevation view of thecamera shown in FIG. 1',

FIG. 4 constitutes an exploded diagrammatic view in perspective of thespread roller assembly of the camera shown in FIG. 1;

FIG. 5 is a diagrammatic, partially cut-away, front elevation view ofthe spread roller assembly of FIG. 4 mounted in the camera of FIG. 1;

FIG. 6 is a view very similar to that of FIG. 5 except that itillustrates the spread roller assembly at such time,-

as a film unit is being advanced therethrough;

FIG. 7 constitutes anenlarged section, partially cutaway, of the spreadroller assembly as depicted in FIG. 6;

FIGS. 8 and 9 diagrammatically represent fragmentary perspective viewsof the film unit container or magazine employed in the camera of FIG. 1;and

FIG. 10 is a view of a section of the camera as shown in FIG. 1 when thecamera is disposed in its collapsed or storage condition.

DESCRIPTION OF TI -IE ILLUSTRATED EMBODIMENT and described inconsiderable detail in aforementioned copending U.S. Pat. applicationSer. No. 134,733 by Edwin H. Land et al. entitled REFLEX CAMERA filedApr. 16, 1971 now U.S. Pat. No. 3,714,879. This camera '10 isillustrated in its extended operative condition in FIG. 1 and in itsstorage or collapsed inoperative condition in FIG. 2. Referring now tothose figures, and FIG. 3, it will be seen that the camera 10 includes aplurality of housing members 12, l4, l6 and 18 which are pivotallycoupled to one another at pivots 20, 22, 24 and 26 forrelativemovementbetween the compact collapsed inoperative condition of FIG. 2and the extended operative condition of FIGS. 1 and 3. Additionally, ahousing member 28 extending in front of the housing member 18 ispivotally'connected thereto, in a manner to be later described, at pivot30 for movement in a clockwise direction as viewed in FIG. 3. In thisconnection, the housing member 28 mounts a spread roller assembly 32including juxtap osed rollers 34 and 36 resiliently urged together by atorsion spring 156 (see FIG. 4). The present invention is particularlyconcerned with the nature of this spread roller assembly 32, ,which willbe discussed in considerable detail hereinafter. r

When the camera 10 is disposed in its extended con dition of FIGS. 1 and3, the spread roller assembly 32 is positioned across an entrance 40 toa film magazine receiving chamber 42. Consequently, the pivotalconnection between the housing members 18 and 28 permits the latter tobe displaced with respect to the former to remove the spread rollerassembly 32 from its blocking position across the. entrance 40 to,facilitate the loading of the camera 10 with a film magazine 44. Eachsuch film magazine 44 includes a plurality of suitable film units 46which, for instance, may take the form of those previously indicated.Additionally, each such film magazine 44 is provided with a pictureframing aperture 48 which, when the magazine is appropriately positionedwithin the receiving chamber 42, is

aligned with the optical system of the camera 10 to facilitate filmexposure operations. Disposed within the film magazine 44 is a springassembly 50 that acts against a plate 52 to continually urge the filmunit 46 closest to the picture framing aperture 48 into the proper focalplane for exposure purposes. An elon- 4 gated opening 54 is provided inthe housing of the film magazine 44 to facilitate the advancement ofeach film unit 46 from the magazine towards the spread roller assembly32 after its exposure.

The member 12 comprises a housing for the cameras lens-shutter assembly56 and an actuator button 58 for initiating camera operations, and isadapted to rotate about the pivot 26 into a position (See FIG. 10) infront of the spread roller assembly 32 adjacent the housing member 28when the camera is rearranged from its extended condition into itscollapsed condition. When the camera is extended as shown in FIGS. 1 and3, the housing members l2, 14, 16 and 18 cooperate with a collapsiblebellows 60 secured thereto to form a sixsided exposure chamber 62.

In addition to an objective lens 63 mounted in the housing member 12,the camera's optical system includes a planar mirror 64 mounted on aninterior wall of the housing member 16 to reflect light rays passingthrough the objective lens towards the cameras focal plane. A plate-likereflex member 66 is pivotally coupled to the housing member 18 at apivot 68. for displacement between its position shown in FIG. 3 whereinit overlies the picture framing aperture 48 and its position shown inphantom in that figure of the drawings wherein it is disposed inoverlying adjacency with respect to the planar mirror 64. This reflexmember.66 includes a viewing surface 70 preferably comprising a suitableFresnel'c'onfiguration and a planar light reflective surface 72. Theoperation of this reflex member 66 will subsequently be set forth inmore detail. The optical system of the camera 10 further includes acollapsible viewing device 74 appropriately mounted to the housingmember 14. This viewing device 74 comprises a curved mirror 76, an eyelens 78 and appropriate housing structure, including telescoping blades80 serving to define a viewing chamber 82 when the viewing device isextended. Appropriate linkages 84 and 86 are included with the viewingdevice 74 to respectively effect the erection of the curved mirror 76and eye lens 78 into their operativepositions responsive to the camerasbeing rearranged from its'collapsed or storage condition into itsextended operative condition.

This unique arrangement of optical elements provides the camera 10 witha single lens reflex characteristicwherein. it is operated first in aviewing and focusing mode and thereafter in an exposure and processingmode. As bestseen in FIG. 3, during the viewing and focusing mode ofoperation, the reflex member 66 rests in light-tight engagement over thefilm magazines picture framingaperture 48. The cameras lens-shutterassembly 56 includes a normally opened shutter which, when the camera isextended, permits image-carrying light rays from the objective lens 63to pass across the chamber 62 to impinge upon the mirror 64 thatreflects such light rays onto the viewing surface 70 of the reflex 14 toimpinge upon a curved mirror 76. This curved mirror 76 includes aconcave ellipsoidal shaped reflecting surface which redirects theselight rays rearwardly through the lens 78 toward an eye station 92. Areal, erect, and unreverted aerial image diagrammatically designated byan arrow 94 is formed by the concave mirror 76 and magnified by the eyelens 78 to facilitate viewing and focusing from the eye station 92. Inthis connection, the housing member 12 additionally serves to mount afocus control knob 96 (See FIG. 1) which may be manually rotated toeffect an appropriate rearward or forward displacement of the lens 63.

To record an image of a subject on the forwardmost film unit 46, thecamers normally opened'shutter is closed and the reflex member 66pivoted into its position shown in phantom in FIG. 3. Thus, when theshutter is subsequently actuated, image-carrying light rays from thesubject enter the cameras chamber 62 through the objective lens 63 andare reflected by the reflective surface 72 of the reflex member 66 ontothe film unit disposed across the picture framing aperture 48 of thefilm magazine 44.

To briefly summarize film exposure operations, the camera is firstarranged into its extended condition with the reflex member 66positioned across the picture framing aperture 48 of the magazine 44.The photographer then views an aerial image of the subject through theeye lens 78 while adjusting the focus control knob 96. Once the image onthe viewing surface 70 of the reflex member 66, as viewed through theviewing device 74, is in sharp focus, the photographer actuates thebutton 58 mounted on the housing member 12. Means (not shown) areincluded in the camera 10 which are responsive to the actuation of thebutton 58 to effect the following sequence of system operations. First,the normally open shutter closes and a blocking member (not shown)covers the aperture 88 in the be]- lows 60 causing the exposure chamber62 to assume a light-tight condition. Next the reflex member 66 ispivoted upwardly within the chamber 62 into its position shown inphantom in- FIG. 3 uncovering the picture framing aperture 48 and thefilm-unit 46 most adjacent thereto. The cameras shutter is then openedto admit image-carrying light rays from the scene into the exposurechamber 62, which'light rays are then reflected by the surface 72 of thereflex member 66 onto the forwardmost film unit 46 to effect therecording of a latent image therein. After an appropriate exposureinterval, the shutter again closes, the reflex member 66 is returned toits initial position wherein it overlies the picture framing aperture 48and the shutterand viewing device aperture 88 are opened. In connectionwith 34 and 36 and from the camera10 through an exit means 100 in thehousing member 28. In this respect, the roller 34 constitutes a driveroller in that. it has a spur gear 102 axially connected thereto whichin turn is coupled to the cameras motor 140 through an appropriate geartrain, not shown in its entirety, but comprising a pinion 106.Additionally, the camera 10 includes a picking mechanism 108 alsoconnected to the cameras motor 104 by anysuitable any suitable (notshown). Preferably, the operation of the aforementioned exposuresequence and the picking mechanism 108 and pinion 106 is automaticallyresponsive to actuation of the button 58. More specifically, depressingthe button 58 first effects an exposure of the film unit 46 in themanner previously described, and, immediately upon the return of thereflex member 66 to its position overlaying the picture framing aperture48, the picking mechanism 108 is actuated to engage the rear edge of theexposed film unit and advance it from the magazine 44 through themagazines opening 54 into the bite of the rotating rollers 34 and 36.The drive roller 34 then serves to progressively advance the film unit46 through the spread roller assembly 32 and thence from the camera 10through its exit means 100.

As the film unit passes between the rollers 34 and 36, the compressiveforce exerted thereon by those rollers first effects a rupturing of apod 112 of processing fluid 114. These rollers 34- and 26 then serve toprogressively distribute the released mass of processing fluid 114across the exposed photosensitive system of the film unit 46 as thatunit progressively passes through the spread roller assembly 32. As thefilm unit 46 emerges from the spread roller assembly 32, it is deflectedby a preferably opaque plate-like member 116 towards the exit means 100.The arrangement of the opaque platelike member 116 and of the exit means100 in cameras of this general type and the functions performed by sameare the subject of the aforementioned concurrently filed copending U.S.patent application Ser. No. 246,703. Briefly stated, film units 46 ofthe type indicated typically include a light transparent outside face orsurface defining layer and the plate-like member 116 is preferablyopaque to light shield sections thereof intermediate the spread rollerassembly 32 and the cameras exit means 100, thereby alleviating fogging"of sections of that film unit yet untreated with the processing fluid114 by the light-piping phenomenon. Since such film units 46 typicallyhave an inherent stiffness, as the exposed film unit is deflectedtowards the exit means 100, progressive sections thereof in advance 7 ofthe rollers 34 and 36 are urged against a subsethese operations, itshould be noted that the camera 10 includes an automatic exposurecontrol system (not shown) which may take any suitable form, having thevcapability of automatically defining the aforemenquently to be describedarrangement of the camera systern to control the movement of the mass offluid 114 across the film units photosensitive system.

'The plate-like member 116 is connected to the housing member 28 atpivot 118 for displacement between its operative position shown in FIG.3 and an inoperative position shown in FIG. 10. Suitable spring means120 continually urges the plate-like member 116 towards its operativeposition of FIG. 3. However, the camera 10 is designed so that, in thecourse of rearranging it from its extended position into its storageposition, its lens-shutter housing 56 engages the plate-like member 116and effects a displacement thereof into its position depicted in FIG.10. At such times, i.e., when the camera is in its collapsed condition,the lens-shutter housing 56 is compactly stored in close adjacency tothe housing member 28.

The cameras exit means 100 is defined by an elongated opening 122 in thehousing member 28 and a resiliently flexible sheet metal component 124which is mounted to the member 28 so as to extend across that opening.As the exposed film unit 46 isadvanced from the spread roller assembly32, it impinges upon the plate-like member 116 which redirects its pathof movement towards the leading and free edge 126 of the sheet metalcomponent 124. In its normal position, the leading edge 126 of thecomponent 124 is positioned in close adjacency to, and preferably seatedagainst, the edge 128 of the opening 122. Thus as the 'film unit 46 isadvanced through the exit means 100, the sheet metal component 124presses the adjacent section of that unit against the edge 128 of theopening 122 thereby serving to grip or retain the film unit once it hascleared the spread roller assembly 32.

' Referring now toFIGS. 8 and 9 of the drawings, it will be seen thatcertain features of the film magazine 44 have been more clearlyillustrated therein. In this respect, the film magazine 44 includes aplurality of specially configured and strategically located projectionsor fingers 130 which in part serve to define the magazines elongatedopening 54. The nature of, the function performed by,and alternatearrangements for, this-feature of the magazine 44 are set forth inconsiderable detail in copending US. application Ser. No. 246,701 byRichard R. Wareham et al. entitled PI-IO- TOGRAPI-IIC PRODUCT ANDAPPARATUS 'filed concurrently with the present application. However, forour present purposes, it will be understood that as each exposed filmunit 46 is advanced from the magazine 44, these projections exert acompressive force thereon at selected positions widthwise thereof. Thus,once the pod 112 of the film unit 46 has been ruptured,

these projections 130 are adapted to control the movement of the mass ofprocessing fluid 114 between, for example, am image-receiving element orlayer and a photosensitive element or system of the exposed film unit 46as it is advanced from the magazine 44. More specifically, theyinfluence or serve to flatten the meniscus of the fluid 1 l4, i.e'., theleading edge of the fluid mass, widthwise of the film unit 46.

Preferably, the film magazine 44 including its projections 130 is formedof an appropriate polymer, such as polystyrene, which is somewhatflexible when molded into relatively thin structures. Under suchcircumstances, the portion 132 of the film magazine 44 from which theprojections 130 depend, has an inherent flexibility. Thus, in ordertopreclude any undesirable flexing of this portion 132 of the filmmagazine 44 during film processing operations, the camera 10 includes arigid support member 134 against which the magazine portion 132 isseated when the magazine is properly positioned within the receivingchamber 42 of the camera. The magazine 44 isalso preferably formed witha finger 136 which assures that only one film unit 46 at a time isadvanced from the magazine 44 towards the rollers 34 and 36 responsiveto the operation of the picking mechanism 108.

The effect of the projections 130 on the mass of processing fluid 102 asthe exposed film unit 46 is advanced therepast is a function of theforces exerted on the film unit by the spring assembly 50 and theplatelike member 116. i

As indicated, the present invention is particularly directed to certainaspects of the camera's spread roller assembly 32, the nature of whichmay best be understood by now referring to FIG. 4 of the drawings. Asshown therein, the assembly 32 comprises 'a spread roll bracket 138preferably formed from a unitary piece of sheet metal such as astainless or carbon steel. This bracket 138 includes a pair of upturnedears 140 and 142 joined together by a central portion 144 comprising asupport 146 and spaced apart substantially parallel flange portions'148and 150. A rigid structural support member 152 is configured to seatagainst the support 146 intermediate the ears 140 and 142 and nestedbetween the flange portions 148 and 150 of the bracket 138. This member152 is preferably formed of any suitable material such as 30-40 percentglass filled thermoplastics such as nylon, polycarbonate,acrylonitrilebutadiene-styrene, polysulfone or glass filledthermosetting phenolic molding compounds, which is light in weightrelative to the material employed to form the bracket 138. A pair ofrivets 154 serve to secure the support member 152 to the bracket 138. Aspecially configured torsion spring 156 rests in tracks 158 of thesupport member 152 with a generally U-shaped central portion 160 thereofextending around a lip 162 formed on the support member and seatedagainst a supporting surface 161 of that member. When the spring 156 ispo sitioned on the support member 152 and the support member connectedto the bracket 138 as indicated, an

elongated projection 163 depending from the bracket's flange portion 150serves to retain the spring in position on the support member. In thismanner the spring 156 is unexposed, i.e.,retained within the confines ofthe bracket 138.

The-roller 36 is hollow and therefore relatively light in weight and oflow inertia, being rotatably mounted on a shaft 164 by a pair of ballbearing assemblies 166 .(See FIG. 7). Respective ends of the shaft164extend through elongated. slots 168 and ,170 provided in the ears 140and 142 of the bracket 138. Flattened ends 172 of the torsion spring 156seat in appropriately positioned annular recesses 174 of the shaft- 164so that the force of that spring continually urges the roller 36 towardsits upwardmost position within the slots 168 and 170 as viewed in FIG.4. It'will be noted that the support member 152 is configuredvwith apair of cutouts 171 to accommodate initial loading of the spring 156 andsubsequent displacement of its flattened ends 172 responsive totranslatory movement of the shaft 164 along the brackets slots l68land170.

' naled to the bracket 138 by ball-bearing assemblies 178 1 mounted inthe brackets ears 140 and 142. Provided on the roller 34 are a pair ofjspaced apart annular collars 180 against which the roller 36 isinitially seated under the force of the torsion spring 156. As bestshown in FIG. 5 of the drawings, these collars 180 determine acontrolled minimum gap 182 between the sheet-contacting facing surfaces184 and 186 of the rollers 34 and 36 which facilitates the initialintroduction of a film unit therebetween. As the film unit 46 isintroduced between the rollers 34 and 36 (see FIG. 6) it effects adisplacement of the roller 36 away from the roller 34 against the forceexerted on the roller 36 by the torsion spring 156. As the exposed filmunit 46 is advanced between the roller: 34 and 36, the compressive forceexerted thereon by same effects a spreading of the processing fluid 114in a layer between two elements or layers 188 and 190 of the film unit.Preferably, the roller 34 is provided with a pair of spaced apartannular recesses 192 strategically positioned as shown to receiveselected portions of specially configured longitudinal edge bindings 194of the film unit 46 in order to preclude the red-framing in accordancewith the teachings of US. Pat. No. 3,647,441 by Albert J. Bachelderentitled PHOTOGRAPHIC APPARATUS AND METHOD issued on Mar. 7, 1972.

It will be appreciated that in this arrangement the force exerted by thetorsion spring 156 is substantially transmitted from the roller 36 tothe roller 34 through the edge bindings 194 of the film unit 46. Thus,by strategically locating the bearing assemblies 166 under these edgebindings 194, i.e., under these longitudinal edges of the film unithaving an increased thickness, as best shown in FIG. 7 and employing ahollow roller 36, deflection of that roller is virtually eliminated, anydeflection in the roller 36 shaft 164 assembly being substantiallyaccommodated by the shaft 164 itself. However, a similar situation doesnot exist in the case of the roller 34 which may experience a certainamount of deflection (diagrammatically depicted in FIG. 6). As a filmunit 46 is advanced lengthwise between the rollers 34 and 36, it isdesired to effect the spreading of a layer of the processing fluid 114thereacross having a substantially uniform thickness. The nature of thelayer of fluid 114 spread by the rollers 34 and 36 is dependent uponmany system parameters including the type of film units, spring forces,deflection of the rollers, profile contours of the sheet-contactingfacing surfaces, etc. One method of providing a uniform fluid layer isto retain certain system parameters constant and vary the profilecontours of the sheet-contacting facing surfaces until the desiredresult has been achieved. In this manner it has been determined insystems of this general type, that a uniform layer of fluid 114 isrealized by employing an initially substantially straightsheet-contacting facing surface 184 on the roller 34 and asheet-contacting facing surface 186 on the hollowroller 36 initiallyhaving a predetermined convex profile configuration (See FIG. 6). Inorder to illustrate this concept and other concepts disclosed herein,certain dimensions have been reflected on FIGS. and 6. However, it is tobe expressly understood that these dimensions are exemplary only and arenot to be interpreted as restricting the scope of the present inventionin any manner.

In this unique arrangement, any frictional forces in the roller 36 shaft164 assembly resulting from twisting or cocking of the bearingassemblies 166 are absorbed by the shaft 164-which is basically anonrotating component. Thus, such frictional forces are not transmittedfrom that assembly back to the battery 98 thereby reducing the load onthat energy source. Most significantly, frictional forces of theassembly 32 have been minimized by providing an arrangement whereinthere is a non-rotating contact between the spring 156 and the shaft164.

One of the advantages of the spread roller assembly 32 is that itprovides for a uniquely compact camera structure. In this context itwill be appreciated that the absolute minimum size of a self-developingcamera is the dimension lengthwise of its fluid spreading elements isdetermined by the width of the film unit processed therein. It istherefore desirable to minimize the overall size ofa spread rollerassembly in the dimension of the length of its rollers to the extentthat it must exceed the length of the sheet-contacting facing surfacesof its rollers. This desired result has been achieved in the spreadroller assembly 32. First, the use of the sheet metal bracket 138, withits relatively thin ears and 142 in combination with the relativelylight and thick rigid structural support member 152 provides for arelatively compact assembly. As indicated, the thickness of the ears 140and 142 may be, and have been, minimized, while the support member 152provides the structural rigidity required by the assembly in a lightweight arrangement. Secondly, since there is only sliding frictionalcontact between the brackets ears 140 and 142 and the roller 36 shaft164 assembly, as opposed to rotational frictional contact therebetween,these considerations place no undesirable burden on the thickness of theears 140 and 142 in the present design. In other words, by minimizingthe frictional forces between the roller 36 shaft 164 assembly and thebracket 138, the thickness of the brackets ears 140 and 142 may beminimized. Thirdly, this arrangement provides spring means 156positioned entirely within the space defined by the brackets ears 140and 142, and the flattened nature of the ends 172 of the spring meanspermits the space which must be provided to accommodate sameintermediate the respective ends of the roller 36 and the inside facesof the ears 140 and 1 42 to be minimized.

Advancement of the film unit 46 through the spread roller assembly 32 isfacilitated by providing the roller 34'with a relatively high frictionfilm driving characteristic. In this context, it is desirable that therelatively high friction be provided with elastomeric types of materialssuch as urethane or rubber. Alternately, high friction non-elastomericmaterials, such as a tungsten carbide alloy, may be employed. It hasalso been found that, in order to effect a smooth transport of anexposed film unit 46 from the film magazine 44 into the bite of therollers 34 and 36, it is desirable to impart rotary motion to therollers 34 and 36 prior to their being engaged by the film unit.Consequently, in the arrangement provided, frictional contact betweenthe collars of the roller 34 and ,the roller 36 impart a rotary motionto the latter roller prior to an exposed film unit 46 being advancedinto the bite of these rollers by the picking mechanism 108. It will berecognized that, where the roller 34 serves to drive the roller 36 inthe manner described, there will be periodic impacts between parts ofthe two rollers. More specifically, as an exposed film unit 46 leavesthe bite of the rollers 34 and 36, the force exerted on the roller 36 bythe torsion spring 156 causes the roller 36 to impact against theannular collars 180 of the roller 34. However, the aforementionedelastomeric materials such as urethane and rubber do not only have thedesirable relatively high friction characteristic but also arerelatively impact sensitive in that, under impact they tend not toretain dimensional stability. Under these circumstances, the

structural integrity of these contacting surfaces of the rollers 34 and36 is enhanced by forming same of relatively low friction, impactresistant materials. Therefore, the roller 36 has been advantageouslyformed of a relatively impact resistant, low friction material such as astainless steel, and a main body portion, including the annular collars180, of the roller 34 has been formed of a similar material. Thesheet-contacting facing surface 184 of the roller 34 comprises a thincoating of, for instance, urethane applied by any suitable process to anappropriate intermediate section of the aforementioned main body portionof the roller 34. This unique arrangement provides the roller 34 with amost desirable relatively high friction sheet-contacting facing surface184 which advantageously is never per,- mitted to contact-the facingsurface 186 of the roller 36, while the contacting surfaces between therollers 34 and 36 comprise impact resistant, relatively low frictionmaterials. Additionally, the use of an elastomeric sheet-contactingfacing surface 184 facilitates the spreading of a uniform layer of thefluid 114 widthwise of the film unit 46 since its resilientlycompressible characteristic accommodates a certain amount of deflectionexperienced by the roller 34. This same characteristic of the facingsurface 184 serves to dampen vibrations of the spreader roller 34thereby facilitating the uniformity of the layer of fluid 114 spreadbetween the elements or layers of the film unit 46. The fact that thefacing surface 184 is precluded from contacting the facing surface 186avoids any compression set of the elastomeric material which wouldadversely affect its ability to spread auniform layer of fluid 114 andincrease the inertia of the roller 34.

It will be seen by referring to FIG. 5 that a plurality of screws 196serve to secure the spread roll bracket 132 to the cameras housingmember 28. As best seen in FIGS. 3 and 4, the pivot 30 is in factdefined by specially configured projections 198 and 200 of the bracketsears 140 and 142, respectively. The projection 198 includes a detent 202which cooperates with complementary releasable latching means (notshown) on the camera when the housing member 28 is in its positiondepicted in FIG. 3 to lock that housing member in its normal functioningrelationship with respect to the other components of the camera. Whenthe camera 10 is in its operative condition, the rear face of thebrackets flange portion-150 serves to locate the film magazine 44 in itsoperative position with-in the cameras receiving chamber42. Forinstance, forward movement of the film magazine 44 responsive to theaction of the picking mechanism 108 islimited by the spread roll bracket32. Thus the spread roll bracket 32 is uniquely configured to maintain apredetermined distance between the rollers 34 and 36 and the meanswithin the camera system, comprising the magazines projections 130, forcontrolling the movement of the mass of pro cessing fluid 114 betweenlayers of the exposed film unit 46 as that unit is advanced from thefilm magazine through the roller assembly 32 and the cameras exit means100. Additionally, the bracket 32 engages the film magazine 44 to retainit in its operative relationship with respect to the cameras lens 63.

The invention has been described for use in connection with a particulartype of film unit and compatible camera structure for illustrativepurposes only. It will be appreciated that it lends itself for use withother types of film, for instance that described in US. Pat. No.3,594,164 by Howard G. Rogers entitled PHOTO- GRAPI-IIC COLORDIFFUSION-TRANSFER PRO- CESS AND FILM UNIT USED THEREIN, and compatiblecamera structure. Additionally this invention may be employed to spreada processing fluid between separate sheets of photographic materials orbetween a film unit and simply a spreader sheet.

Those familiar with the photographic arts will readily appreciate thenovel and highly unique'advantages of this invention. Most importantly,a filmadvancing spread roller system has been provided having structuralintegrity with unusually efficient means for effecting a rotation of therollers prior to the introduction of an exposed film unit therebetweenand for subsequently effecting the advancement of the film unittherethrough.

This invention may be practiced or embodied in still other ways withoutdeparting from the spirit or essential character thereof. The embodimentdescribed herein is therefore illustrative and not restrictive, the

scope of the invention being indicated by the appended claims and allvariations which come within the meaning of the claims are intended tobe embraced therein.

What is claimed is:

l. Photographic apparatus for spreading a processing fluid in a layerbetween a pair of elements of a given width, at least one of suchelements forming part of a film unit, said apparatus comprising:

a first rotatably mounted elongated spreader roller having a firstsheet-contacting facing surface at least equal in length to the givenwidth of such pair of elements and including a relatively high friction,resiliently yieldable sheet-contacting facing surface;

a second rotatably mounted elongated spreader roller having a secondsheet-contacting facing sur face, said second spreader roller beingmounted with its said secondsheet-contacting facing surface juxtaposedwith respect to said first sheetcontacting facing surface;

means for yieldably urging said spreader rollers towards one another;

means for limiting the movement of said spreader rollers towards oneanother under the influence of said urging means to define a minimum gapbetween said first and second sheet-contacting facing surfacesfacilitating the introduction therebetween of such pair of elements,said movement limiting means including a pair ofiannular collarsprovided with bearing surfaces mounted on one of said rollers andextending towards the other said roller, and supporting surfaces on saidother roller to respectively engage said collar bearing surfaces, saidbearing surfaces and said supporting surfaces comprising relativelylow-friction, non-resilient surfaces tending to preserve theirdimensional integrity, said annular collars being spaced apart adistance greater than such given width and respectively located adjacentopposite ends of said first sheet-contacting facing surface; and l meansfor driving said first spreader roller to cause said movement limitingmeans to impart rotary motion to said second roller prior to theintroduction of such pair of elements between said spreader rollers andto cause said relatively high friction, resiliently yieldablesheet-contacting facing surface to advance such pair of elements betweensaid rollers intermediate said collars once such pair of elements havebeen brought into operative relationship therewith, said collars beingrendered inoperative for purposes of defining the spacing between saidsheet-contacting facing surfaces as such pair of elements are advancedbetween said rollers.

with said supporting surfaces.

3. The apparatus of claim 2 wherein said relatively high friction,resiliently yieldable, impact sensitive sheet-contacting facing surfacecomprises urethane and said bearing surfaces and supporting surfacescomprise a stainless steel.

1. Photographic apparatus for spreading a processing fluid in a layerbetween a pair of elements of a given width, at least one of suchelements forming part of a film unit, said apparatus comprising: a firstrotatably mounted elongated spreader roller having a firstsheet-contacting facing surface at least equal in length to the givenwidth of such pair of elements and including a relatively high friction,resiliently yieldable sheetcontacting facing surface; a second rotatablymounted elongated spreader roller having a second sheet-contactingfacing surface, said second spreader roller being mounted with its saidsecond sheet-contacting facing surface juxtaposed with respect to saidfirst sheetcontacting facing surface; means for yieldably urging saidspreader rollers towards one another; means for limiting the movement ofsaid spreader rollers towards one another under the influence of saidurging means to define a minimum gap between said first and secondsheet-contacting facing surfaces facilitating the introductiontherebetween of such pair of elements, said movement limiting meansincluding a pair of annular collars provided with bearing surfacesmounted on one of said rollers and extending towards the other saidroller, and supporting surfaces on said other roller to respectivelyengage said collar bearing surfaces, said bearing surfaces and saidsupporting surfaces comprising relatively low-friction, non-resilientsurfaces tending to preserve their dimensional integrity, said annularcollars being spaced apart a distance greater than such given width andrespectively located adjacent opposite ends of said firstsheet-contacting facing surface; and means for driving said firstspreader roller to cause said movement limiting means to impart rotarymotion to said second roller prior to the introduction of such pair ofelements between said spreader rollers and to cause said relatively highfriction, resiliently yieldable sheet-contacting facing surface toadvance such pair of elements between said rollers intermediate saidcollars once such pair of elements have been brought into operativerelationship therewith, said collars being rendered inoperative forpurposes of defining the spacing between said sheet-contacting facingsurfaces as such pair of elements are advanced between said rollers. 2.The apparatus of claim 1 wherein said relatively high friction,resiliently yieldable sheet-contacting facing surface is relativelyimpact sensitive and said relatively low friction, non-resilient bearingand supporting surfaces are relatively impact insensitive tending topreserve their structural integrity during extensive operation of saidapparatus wherein said urging means repetitively returns said bearingsurfaces into contact with said supporting surfaces.
 3. The apparatus ofclaim 2 wherein said relatively high friction, resiliently yieldable,impact sensitive sheet-contacting facing surface comprises urethane andsaid bearing surfaces and supporting surfaces comprise a stainlesssteel.